package com.kuang.pc;

/**
 * Author: Zhang Dongwei
 * Date: 2022/3/13 10:29
 */

/**
 * 线程之间的通信问题：生产者和消费者问题! 等待唤醒，通知唤醒
 * 线程交替执行 A B操作同意变量，num=0
 * A num+1
 * B num-1
 */
public class A {
    public static void main(String[] args) {
        Data data = new Data();

        new Thread(()->{
            for (int i = 0; i< 10; i++){
                try {
                    data.increment();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }, "A").start();

        new Thread(()->{
            for (int i = 0; i< 10; i++){
                try {
                    data.decrement();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }, "B").start();

        new Thread(()->{
            for (int i = 0; i< 10; i++){
                try {
                    data.increment();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }, "C").start();

        new Thread(()->{
            for (int i = 0; i< 10; i++){
                try {
                    data.decrement();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }, "D").start();

    }
}

// 判断等待，业务，通知
class Data{// 数字，资源类

    private int number = 0;

    //+1
    public synchronized void increment() throws InterruptedException {
        while (number!=0){
            //等待
            this.wait();
        }
        number ++;
        System.out.println(Thread.currentThread().getName()+"=>"+number);
        //通知其他线程，我+1完毕了
        this.notifyAll();
    }

    //-1
    public synchronized void decrement() throws InterruptedException {
        while (number == 0){
            //等待
            this.wait();
        }
        number --;
        System.out.println(Thread.currentThread().getName()+"=>"+number);
        //通知其他线程，我-1完毕了
        this.notifyAll();
    }
}